JP3165370B2 - Method for manufacturing plasma display panel - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for manufacturing a plasma display panel (hereinafter referred to as PDP),
More specifically, a method of manufacturing a PDP capable of forming a barrier and / or an insulating layer for reflecting visible light (hereinafter referred to as a reflective layer) that is excellent in dimensional accuracy and positional accuracy and that can be miniaturized by photolithography. About.

[0002]

2. Description of the Related Art FIG. 1 is a perspective view showing an example of a DC PDP among PDPs. This PDP comprises a front insulating plate 1 arranged in parallel and opposite to each other with a certain space therebetween.
And a rear insulating plate 2. Inside the insulating plates 1 and 2, an anode electrode group (anode) 3 and a cathode electrode group (cathode) 4, which face each other and intersect, are provided. A barrier 5 for forming a display cell 6 and an auxiliary cell 7 is provided at a portion orthogonal to the area between the display cells 4. The barrier 5 is provided to form the display cell 6 and the auxiliary cell 7, to prevent light crosstalk between the electrode groups 3 and 4, and to keep the gap between the front insulating plate 1 and the rear insulating plate 2 constant. ing. In addition, the surface of the back insulating plate 2 facing the front insulating plate 1 (the bottom of the back insulating plate 2)
An electrode group 3 having a thickness of about 10 to 30 μm and corresponding to each display cell 6 of the reflection layer 8 and involved in discharge.
A discharge window 9 is provided on the display anode 3a. A rare gas is sealed between the two electrode groups 3 and 4, and the intersection of the two electrode groups 3 and 4 corresponds to one pixel (display cell 6). Here, in order to perform uniform discharge, it is necessary that the discharge window 9 be a window having excellent dimensional accuracy and less variation in shape. 3b is the auxiliary cell 7
It is an auxiliary anode that controls the pilot discharge.

In this PDP, when a voltage is applied between the electrode groups 3 and 4, a discharge occurs, and the display cell 6 receives a supply of charged particles and the like from a pilot discharge in the auxiliary cell 7 and has an internal display. A discharge is formed and ultraviolet light is generated. The fluorescent screen (red fluorescent screen 11, green fluorescent screen 12, blue fluorescent screen 13) of the display cell 6 excited by the ultraviolet light
Obtain visible light from In this color PDP, luminous efficiency,
From the viewpoint of improving brightness, a phosphor is applied to the inner wall of the display cell 6 and / or the surface of the rear insulating plate 2 facing the front insulating plate 1, and visible light reflected from the phosphor is used for display. Thereby, the visible light from the barrier 5 and / or the reflective layer 8 can be used efficiently.

Conventionally, the barrier 5 and the reflective layer 8 of the PDP are formed by a thick film forming method. However, this thick film forming method has a problem that it is difficult to obtain a reflective layer that is satisfactory in terms of dimensional accuracy, positional accuracy, and shape, and cannot cope with miniaturization of a barrier width. So, in recent years,
From the viewpoint of miniaturization of the barrier width, improvement of the dimensional accuracy, and securing of positional accuracy in increasing the size, formation of a barrier or a reflective layer using a photolithography method has been attempted (JP-A-2-165538). Gazette). In this formation method, the pattern portion was selectively irradiated with ultraviolet rays using a light-shielding mask and cured by applying a light-shielding mask to a coating film of a photosensitive paste in which a ceramic powder and an ultraviolet-curable resin were mixed, and this process was repeated a plurality of times, thereby being laminated. In this method, a coating layer is obtained, and the coating layer is collectively developed and baked to form a predetermined pattern. According to this method, a line width and a line interval of 100 μm or less and 100 μm
A barrier for a PDP having the above height can be formed, and a reflective layer having a desired height can be obtained.

[0005]

However, the aforementioned PD
When the P barrier and the reflection layer are formed by photolithography using a photosensitive paste, there are the following problems. That is, (1) In order to form a barrier or a reflection layer, it is preferable that the raw material ceramic powder is white. This is because visible light can be used efficiently by using a white insulator for the barrier and the reflective layer. However, since the white powder has a high reflectance, the scattering of ultraviolet light in the photosensitive paste at the time of exposure increases, the width of the formed pattern becomes wider than the design pattern width, and the uniform shape decreases the dimensional accuracy. I can't get it. (2) In addition, ultraviolet rays that have passed through the coating layer and reached the surface of the substrate (back insulating plate) on which the coating layer was formed are reflected on the substrate surface to expose unexposed portions on the substrate surface. However, since the peripheral portion of the pattern is also exposed and cured at the same time, a hardened residue that is hard to develop remains in the peripheral portion of the pattern, which adversely affects dimensional accuracy and miniaturization of the shape. (3) Therefore, it is not possible to form a barrier or a reflective layer (discharge window) having excellent dimensional accuracy, positional accuracy and shape, and there is a limit to increasing the definition and size of a PDP. There is a problem that.

[0006] In view of such problems, the present inventor has conducted various studies. As a result, it has been found that, by including an ultraviolet absorber in the photosensitive paste, the scattering of ultraviolet light during the exposure can be reduced. I found out. The present invention has been made in view of such a problem, and a purpose thereof is to use a photolithography method to suppress an exposure spread of a coating layer, to have excellent pattern dimensional accuracy, and to have a shape variation. It is an object of the present invention to provide a method of manufacturing a PDP having a small barrier and / or a reflective layer and improved display quality and high yield.

[0007]

According to a first aspect of the present invention, there is provided a method of manufacturing a plasma display panel according to the present invention. A plasma display panel provided with two sets of electrodes that face each other and intersect each other inside the front insulating plate and the rear insulating plate, and a barrier for forming a discharge cell at a portion orthogonal to the two electrode groups. In the manufacturing method, the barrier is formed by a photolithography method using a photosensitive paste containing an ultraviolet absorber, and an insulating layer for visible light reflection is formed on a surface of the back insulating plate facing the front insulating plate. And the insulating layer is formed by a photolithography method using a photosensitive paste containing an ultraviolet absorber. According to a second aspect of the present invention, there is provided a method of manufacturing a plasma display panel according to the first aspect, wherein the ultraviolet light absorber comprises an azo organic dye.

In the present invention, in the PDP of FIG. 1 described in the prior art, the barrier and / or the reflective layer are formed by a photolithography method using a photosensitive paste containing an ultraviolet absorber. Here, as the photosensitive paste, a paste composition in which an ultraviolet absorber, a photosensitive resin, and a solvent are mixed is used. By including an ultraviolet absorber in the photosensitive paste, it is possible to suppress adverse effects on barriers and reflection layer pattern formation due to scattering and reflection of ultraviolet rays.
That is, high resolution can be obtained by including a light absorbing agent having a high ultraviolet light absorbing effect.

Here, as the ultraviolet light absorbing agent, 45
It is necessary that it absorbs light of 0 nm or less and is itself stable to light and does not absorb visible light. In addition to satisfying this condition, it evaporates and decomposes at the time of firing to reduce the insulation resistance. Organic dyes that do not have to be reduced are preferred. As the organic dye, various dyes having a high absorbance can be used, and examples thereof include azo dyes, anthraquinone dyes (anthraquinone mordant dyes, anthraquinone acid dyes), and xanthene dyes (pyronine dyes and stylen dyes). It can be used, among which azo dyes are preferred. The azo dye can be obtained relatively easily and inexpensively, and a stable dye suitable for the purpose can be selected from various combinations of components.

As the azo dyes, azo dyes,
Acid azo dyes, acid mordant azo dyes, metal complex salt azo dyes,
Reactive azo dyes, disperse azo dyes, azoic dyes, oil-soluble azo dyes and the like can be used. Specific examples of preferred azo dyes include Direct Yellow-12, Acid Yellow 23, Mordant Orange 1, Reactive・ Yellow 3, Disperse Yellow 3, Sudan I, Sudan II, Sudan III, Sudan IV, Sudan Blue G
L, Orange I, Orange SS, Oil Yellow OB,
Oil Yellow AB, Black 2 IIB, Naphthol Yellow S, Acid Red 52, New Coxin, Benzopurpurin 4B, Chloratin Fast Red 5B, and the like. Among them, Sudan IV and Oil Yellow O
B is particularly preferred. Here, the amount of the organic dye added is determined by the type, particle size, and the like of the ceramic powder,
The range is 0.01 to 5% by weight, preferably 0.02 to 0.2% by weight based on the ceramic powder. If the amount is less than this range, the effect of the addition of the organic dye is not recognized. If the amount is too large, the absorption of ultraviolet rays is excessively increased and the efficiency is inefficient.

As the photosensitive resin, conventionally known photosensitive resins can be used, for example, a diazo resin having a diazo group as a photosensitive group, an aromatic azide resin having an azide group as a photosensitive group, and a carboxyl group in a side chain. And an acrylic copolymer having an ethylenically unsaturated group. The coating layer to which the photosensitive paste containing the photosensitive resin is applied is a layer that is insolubilized or solubilized by irradiating with an active light beam. In addition, as the solvent, ethylene glycol-n-butyl ether acetate or the like can be used.

In the present invention, the photosensitive paste is used by mixing with a ceramic powder. The ceramic powder is not particularly limited, and any known ceramic insulating material for low-temperature firing or the like can be used, and examples thereof include ceramic powder alone, a glass-ceramic composite system, and crystallized glass. When the ceramic powder is used alone, there are powders of alumina, zirconia, magnesia, mullite, cordierite, anorthite, silica, clinoenstatite, aluminum nitride, and the like, or low-temperature fired ceramic powder. Examples of glass-ceramic composite systems include silica,
Glass composition powder containing alumina, calcia, boria and, if necessary, magnesia, titania, etc., and one or a mixture thereof selected from the group consisting of alumina, zirconia, magnesia, mullite, cordierite, anorthite, silica and aluminum nitride There is. The particle size and specific surface area of the ceramic powder are selected in consideration of the thickness of the barrier and / or reflective layer to be produced and the shrinkage after firing.

In addition to the above-mentioned photosensitive resin, ultraviolet light absorber and solvent, the above-mentioned photosensitive paste may further contain a stabilizer, a sensitizer, a sensitizing aid, a photopolymerization accelerator, A polymerization inhibitor, a plasticizer, an antioxidant, a dispersant, an organic or inorganic precipitation inhibitor, and the like are appropriately added.

[0014]

As is apparent from the above description, in the method for manufacturing a plasma display panel according to the first aspect of the present invention, it is possible to suppress the spread of exposure and to form a barrier without residue without deteriorating adhesion. In addition, it is possible to obtain a reflective layer in which variations in pattern dimensions and shapes are suppressed,
The barrier can be whitened by a photolithography method using a photosensitive paste, so that the brightness and the luminous efficiency of the PDP can be improved, and the variation in discharge can be suppressed and the display quality can be improved. In addition, since the photolithography method is used, a fine barrier and / or a reflective layer can be formed, so that there is an effect that a large-sized and high-definition PDP can be manufactured with high yield.

In the method of manufacturing a plasma display panel according to the second aspect, since an organic dye is used as an ultraviolet light absorber, high absorbance can be obtained in the process of forming a barrier or a reflective layer by photolithography. And the organic dye evaporates during firing and disappears after firing, so in the formed barrier and reflective layer,
Insulation, denseness and whiteness can be prevented from deteriorating due to the ultraviolet absorber, and since the azo organic dye is used as the organic dye, the ultraviolet absorber can be obtained relatively easily and inexpensively. In addition, there is an effect that a stable dye suitable for the purpose can be selected from various combinations of components.

[0016]

Next, a preferred embodiment of the method for producing a PDP of the present invention will be described. As the PDP, there are a DC PDP as shown in FIG. 1 described above and various DC and AC PDPs. P of the present embodiment
The DP manufacturing method is characterized in that the barrier and / or the reflective layer are formed by a photolithography method using a photosensitive paste containing an ultraviolet absorber. As for other configurations, as described in the related art, the manufacturing is performed using the method disclosed in Japanese Patent Application Laid-Open No. 2-165538. In the present embodiment, the barrier and the reflection layer are formed of a white insulator.

In the embodiment of the present invention, the photosensitive paste having the above characteristics is used in an amount of 10 to 70% by weight, particularly preferably 30 to 50% by weight, based on 100 parts by weight of the ceramic powder. If the amount is too small, the pattern cannot be formed due to insufficient ultraviolet curing, and if the amount is too large, the shrinkage increases, the number of laminating steps increases, and the compactness further deteriorates. The ultraviolet light absorber contained in the photosensitive paste is based on 100 parts by weight of the ceramic powder.
The range is preferably 0.01 to 5% by weight, particularly preferably 0.02 to 2% by weight. This is because if the amount is less than this, the effect of addition is not recognized, and if it is more than this, absorption of ultraviolet rays proceeds excessively and the efficiency is inefficient. Further, as the ultraviolet absorbent, an organic dye, particularly, an azo organic dye is preferable. By using the azo-based organic dye, a high absorbance can be obtained, and since it evaporates during firing and does not remain in the ceramic after firing, the insulating property of the formed barrier and / or reflective layer due to the ultraviolet absorber is reduced. , Denseness and whiteness can be prevented from lowering. Exposure is performed using a parallel light with a mercury lamp as a light source. After exposure, development is performed using a developing solution to remove portions that are not photocured, and the aspect ratio is 1 to 5, preferably 2 to 3. Form a live barrier pattern of the area. Here, the height of the barrier before exposure is 100
５００500 μm, the height of the reflection layer before exposure is 15-50 μm
m. As a developing method, an immersion method or a spray method is used.As the developing solution, an alkaline aqueous solution or an organic solvent in which an uncured material can be dissolved can be used.
Water may be added to the organic solvent as long as its solubility is not lost. Next, firing is performed in a firing furnace to form a barrier. Here, the firing atmosphere and the firing temperature vary depending on the type of the insulating plate and the conductor.

When a photosensitive paste having the above composition is used, in the step of forming a barrier and a reflective layer using a photolithography method, exposure spread can be suppressed, and a fine pattern which does not impair the adhesion to the back insulating plate can be obtained. It was possible to form a reflective layer and a discharge window in which variations in pattern, pattern size and shape were suppressed, and a PDP with improved display quality could be manufactured with high yield.

It should be noted that the present invention is not limited to the above-described embodiment, and includes a configuration that can be modified and implemented without changing the gist of the present invention. In the examples described later, each of the barrier and the reflective layer is shown, but this pattern is formed by obtaining the reflective layer and then forming the barrier.
A better PDP can be obtained. In the examples described below, the composition of the ceramic powder is limited. However, the present invention can be effectively implemented by optimizing the type and amount of the organic dye for any ceramic powder. By the way, the present invention is not limited to the DC type PDP,
It can also be applied as a method for forming a barrier in an AC type PDP. Further, the shape of the barrier and / or the reflective layer is not particularly limited, and may be, for example, a stepped, mortar-shaped, or circular reflective layer discharge window as long as the function can be exhibited.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, in the method for producing a PDP of the present invention,
Examples 1 to 3 and Comparative Example 1
According to the above-described embodiments, the method for forming the reflective layer is described in Examples 4 to 6,
This will be described more specifically with reference to Comparative Examples 4 to 6. In the following description, the amounts used and the proportions are all expressed by weight. Raw materials A. Ceramic powder (1) Barrier: A raw material comprising 20 parts of 99.8% purity alumina powder and 80 parts of lead borosilicate glass composition powder was used. The alumina powder had an average particle size of 1.5 μm, a specific surface area of 4.0 m ² / g, and the glass composition was PbO: 50 to 70.
_{%, B 2 O 3: 15~25} %, SiO 2: 8~25%,
Al ₂ O ₃ : 1 to 10%. After fritting at 1200 ° C., it was pulverized with a ball mill. Average particle size 3.0
μm and a specific surface area of 1.5 m ² / g. (2) Reflective layer: A raw material comprising 99.8% pure alumina powder 20%, lead borosilicate glass composition powder 65%, and titanium powder 15% was used. Alumina powder has an average particle size of 1.5μ
m, specific surface area 4.0 m ² / g, titanium powder average particle size 0.5 μm, specific surface area 20 m ² / g or more, glass composition: PbO: 50 to 70%, B ₂ O ₃ : 15 to 25% ,
_{SiO 2: 8~25%, Al 2} O 3: was 1-10%. After fritting at 1200 ° C., it was pulverized with a ball mill. Average particle size 3.0 μm, specific surface area 1.5 m ² / g
Met. B. Organic Dyes As an azo organic dye, Sudan IV (chemical formula: C ₂₄ H ₂₀
Oil yellow OB (chemical formula: CH ₃ C ₄ H ₄ ) as an N ₄ O, a molecular weight of 380.5) and an azo organic dye.
N, molecular weight 261.3). C. Photosensitive resin A commercially available photopolymerizable liquid resist that can be developed with an aqueous alkaline solution was used. D. Solvent Ethylene glycol-n-butyl ether acetate was used.

Examples 1 to 3 and Comparative Examples 1 to 3 (Preparation of Photosensitive Paste) The preparation of the paste was carried out by adding an azo organic dye (organic dye and organic dye) to 100 parts by weight of the above-mentioned ceramic powder. 005% to 10% and 40% (in terms of solid content) of the photosensitive resin were mixed and adjusted for 10 minutes by a planetary mill. The solvent was appropriately mixed to adjust the viscosity of the paste.

(Formation of Barrier Pattern) a. Paste application A photosensitive paste for forming a barrier was applied by a roll coater on a glass plate (back insulating plate) provided with electrodes, resistors, and a reflective layer. b. Exposure The coating layer was irradiated (exposed) with ultraviolet light having a wavelength of 420 nm using an ultra-high pressure mercury lamp to selectively cure the barrier forming portion.
This coating-exposure process was repeated several times until the desired thickness of the barrier was reached. Examples 1-3 and Comparative Examples 1-3
Then, a raw thickness of 150 μm was obtained. c. Development The exposed and laminated photosensitive paste coating layer prepared above was developed under the conditions of a Na ₂ CO ₃ concentration of 1%, a temperature of 30 ° C., and a spray pressure of 2 kg / cm ² to obtain a barrier pattern. d. Firing The barrier pattern obtained by the above process is 520 ° C. × 15
Baking for 10 minutes to volatilize the organic components in the barrier pattern and form a vitrified height of only inorganic components on the glass plate of 12
A white barrier of 0 μm was obtained.

(Evaluation of Barrier Pattern) In each of Examples 1 to 3 and Comparative Examples 1 to 3, the residue on the fired barrier pattern, the vitrification state of the ceramic powder, the adhesion to the glass plate, and the interlayer between the coating films were determined. The adhesion and the measured barrier width at a mask dimension of 50 μm were observed and measured. Table 1 shows the results.

[0024]

[Table 1]

As shown in Table 1, the obtained Examples 1 to 3
In the barrier pattern, no problems were observed in the vitrification state of the ceramic powder, the adhesion to the glass plate, the adhesion between the coating layers, and no residue was observed. The increase in the barrier width due to the exposure is the same as the amount of shrinkage in firing, and the barrier width is 50 μm.
was gotten. By suppressing the spread of exposure in this manner, the barrier pattern can be miniaturized. On the other hand, when the addition amount of the organic dye is out of the appropriate range, and in the barrier patterns of Comparative Examples 1 to 3 where the inorganic dye is added, when the addition amount of the organic dye is more than 5%, the transmission of the ultraviolet ray is sufficient. No peeling of the pattern was observed between the coating layer and the glass substrate during development, and when the amount of the organic dye added was less than 0.01%, scattering and reflection of ultraviolet rays were not suppressed, and residues remained on the glass substrate. When an inorganic dye was added, it was confirmed that vitrification and whitening of the barrier were inhibited, and a dense and white barrier pattern could not be obtained.

Examples 4 to 6, Comparative Examples 4 to 6 (Reflection layer pattern formation) a 'Paste coating Roll a photosensitive paste for forming a reflection layer on a glass plate (back insulating plate) provided with electrodes and resistors. It was applied by a coater. b 'Exposure After the above-mentioned coating, ultraviolet rays having a wavelength of 420 nm were irradiated with an ultra-high pressure mercury lamp (exposure was performed to selectively cure the reflective layer forming portion).
This process from coating to exposure was repeated several times until the desired thickness of the reflective layer was obtained. Examples 4 to 6, Comparative Examples 4 to 6
Then, a raw thickness of 40 μm was obtained. c ′ Development The exposed and laminated photosensitive paste coating layer prepared above was developed under the conditions of a Na ₂ CO ₃ concentration of 1%, a temperature of 30 ° C., and a spray pressure of 2 kg / cm ² to obtain a reflective layer pattern. d ′ baking The reflection layer pattern obtained by the above process was 535 ° C. × 1
After baking for 5 minutes, the organic component in the reflective layer pattern was volatilized to obtain a vitrified white reflective layer consisting of only the inorganic component and having a height of 30 μm.

(Evaluation of Reflective Layer Pattern) Residue, adhesion to glass plate, and measured discharge window size and variation when the mask size of the discharge window diameter was φ150 μm were observed and measured for the fired reflective layer pattern. Table 2 shows the results.

[0028]

[Table 2]

As shown in Table 2, in the reflection layer wall patterns obtained in Examples 4 to 6, no problem was observed in the adhesion to the glass plate, and no residue was observed. In addition, it was confirmed that a reduction in the diameter of the discharge window of the reflective layer due to the spread of the exposure can be suppressed, a uniform discharge window shape and size can be obtained, and the diameter of the discharge window can be reduced. On the other hand, in the reflective layer patterns of Comparative Examples 4 to 6, the amount of the organic dye added was 5%.
%, Ultraviolet rays were not sufficiently transmitted, and the pattern was peeled off from the glass substrate during development. When the amount of the organic dye added is less than 0.01% or when an organic dye having a low absorbance is used, the scattering and reflection of ultraviolet rays cannot be suppressed and the discharge window is crushed or the diameter of the discharge window varies, resulting in a uniform discharge window. No discharge was obtained.

[Brief description of the drawings]

FIG. 1 shows a DC type PDP among PDPs according to the present invention.
It is a perspective view of the basic structure of an example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Front insulating plate, 2 ... Back insulating plate, 3 ... Anode electrode group (anode), 3a ... Display anode, 3b ...
・ Auxiliary anode, 4 ・ ・ ・ Cathode group (cathode), 5 ・ ・
・ Barrier, 6 ・ ・ ・ Display cell, 7 ・ ・ ・ Auxiliary cell, 8 ・ ・
・ Reflection layer, 9 ・ ・ ・ Discharge window, 11 ・ ・ ・ Red phosphor screen, 12 ・ ・ ・ Green phosphor screen, 13 ・ ・ ・ Blue phosphor screen

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01J 9/02 H01J 17/04

Claims (2)

(57) [Claims] 1. A pair of mutually intersecting electrode groups are provided inside a front insulating plate and a rear insulating plate which are arranged in parallel with each other and opposed to each other with a certain space therebetween. In a method for manufacturing a plasma display panel provided with a barrier for forming a discharge cell in a portion orthogonal to the above, the barrier is formed by a photolithography method using a photosensitive paste containing an ultraviolet absorber, and A plasma characterized in that an insulating layer for reflecting visible light is provided on a surface of the insulating plate facing the front insulating plate, and the insulating layer is formed by a photolithography method using a photosensitive paste containing an ultraviolet absorber. Display panel manufacturing method. 2. The method for manufacturing a plasma display panel according to claim 1, wherein the ultraviolet light absorber is an azo organic dye.